Field of the Invention
The present invention generally relates to improved patent interfaces, particularly but not solely, for use in delivering artificial respiration therapy to users or wearers of the patient interfaces, such as patients. In particular, certain features, aspects of embodiments of the present invention relate to mask assemblies of such interfaces and headgear assemblies used to secure the mask assemblies to a patient.
Description of the Related Art
In the art of respiration devices, there are a variety of respiratory interfaces that cover the nose and/or mouth of a patient in order to provide a seal around the nasal and/or oral areas of the face such that gas may be provided at positive pressure within the interface for consumption by the patient.
The interfaces must provide an effective seal against the face to reduce the likelihood of significant leakage of the respiratory gas being supplied. In many interfaces, a good seal often is attained only with considerable discomfort for the patient, with temporary success and/or with significant time spent fitting the interface to the patient.
With respect to the discomfort for the patient, this problem is most crucial in acute care medical environments. In such environments, the patient will be required to wear the interface continuously for hours or perhaps even days. If significant discomfort is experienced, the patient will not willingly tolerate the mask for the desired long durations.
In many constructions, even a good seal can be temporary due to an inability to seal effectively when the face of the patient becomes distorted. For example, when the patient is sleeping on a side, one side of the headgear may be pulled tight while the other side becomes loose. This asymmetric loading can twist the axis of the interface relative to the axis of the head due to the net torque from the headgear and any associated breathing tube. The twisting of the axis can result in leakage on one side of the interface. In addition, a side-sleeping patient may also distort the facial contours (e.g., in the nasal area) around the seal, which may lead to further leakage.
Finally, in acute care settings, the speed with which respiratory treatment can be established is important. Accordingly, with some headgear configurations, the ability to rapidly establish a satisfactory seal has been identified as an area in which current configurations could be improved.